Filter apparatus

ABSTRACT

A filter device having a filter housing (1), having a fluid inlet (11) for unfiltered matter and having a fluid outlet (19) for filtered matter and at least one filter element (7, 9) of one or more parts accommodated in the filter housing (1), which filter element can be cleaned using at least one backwash element (21) in counter current to the direction of filtration, which can be moved by means of a fluid-conveying drive shaft (20) of a rotary drive at the inside (17) of the relevant filter element (7, 9) and which has, at the end adjacent to this inside (17), a gap-shaped passage opening, which is parallel to the axis of rotation (16) of the drive shaft (20) and which opens into a flow chamber connected to the drive shaft (20) in a fluid-conveying manner, is characterized in that the distance between the backwash element (21) and the adjacent assignable filter element (7, 9) can be predetermined by means of an adjustment device (27; 47).

The invention relates to a filter device having a filter housing andhaving a fluid inlet for unfiltered matter and having a fluid outlet forfiltered matter and at least one filter element of one or more partsaccommodated in the filter housing, which filter element can be cleanedusing at least one backwash element in counter current to the directionof filtration, which can be moved by means of a fluid-conveying driveshaft of a rotary drive at the inside of the relevant filter element andwhich has, at the end adjacent to this inside, a gap-shaped passageopening, which is parallel to the axis of rotation of the drive shaftand which opens into a flow chamber connected to the drive shaft in afluid-conveying manner.

The perfect condition of the lubricating oil is of great importance forthe operational safety and service life of internal combustion engines.In particular, the continuous operation of diesel engines, which areoperated using heavy fuel oil for instance in maritime applications,makes particularly high demands at the characteristics of thelubricating oil, i.e. the use of filter devices for lubricating oilpurification is essential in such applications. In this regard, it isstate of the art to use filter devices, in which filter cartridges arebackwashed to allow longer run times between changes of filtercartridges and to keep maintenance costs low in that way. As examples ofthe related state of the art, the documents DE 34 43 752 A1 and DE 20216 012 206 U1 show filter devices of the type mentioned above.

Based at this state of the art, the invention addresses the problem ofproviding a filter device of the type mentioned at the outset, which ischaracterized by a high efficiency of cleaning and a particularly highlevel of operational reliability.

According to the present invention, this object is achieved by a filterdevice having the features of claim 1 in its entirety.

According to the characterizing part of claim 1, a significant featureof the invention is that the distance between the backwash element andthe adjacent assignable filter element can be predetermined by means ofan adjustment device. The option of adjusting the backwash element tothe relevant filter element provides tolerance compensation, whichpermits an optimum distance-free contact of the gap-shaped passageopening of the respective backwash element at the wall of the filtermaterial even for deviations within the usual tolerance ranges. As aresult, the filter device according to the invention is distinguishednot only by a particularly high efficiency of cleaning achieved duringthe backwashing process, but also by a high degree of operationalreliability.

In advantageous exemplary embodiments, the adjusting device has aspindle drive, which can be actuated manually from one side of the driveshaft and has closing means, which act at the other side of the driveshaft at the respective backwash elements.

Advantageously, the arrangement may in this case be such that thespindle of the spindle drive executing its adjustment motion extendsthrough the inner fluid guide of the drive shaft and its end extendingthrough the drive shaft forms the part of the dosing means acting at theindividual backwash element.

Alternatively, dosing mean, that can be moved by the spindle drive canbe guided past outsides of the drive shaft, wherein the ends of thisdosing means routed to the other side also act on the backwash element.

The backwash element may have a receiving housing, with which thespindle drive engages with its respective dosing means and in which theat least two partial backwash elements are accommodated, wherein onefluid guide is assigned to every partial element, which, guidedlongitudinally, engages in every traversing position of the receivinghousing with the internal fluid guide of the drive shaft. The fluidguides of the partial elements can be formed by telescopically movablepipe parts, one of which is connected to the relevant partial elementand the other to the inner fluid guide of the drive shaft.

In embodiments, in which the spindle drive is fed through the driveshaft, its respective dosing means can act on the receiving housingbetween the fluid guides of a pair of partial elements.

In the case of closing means guided laterally past the drive shaft, therespective dosing means for every partial element may be movably guidedin every guide housing mounted at the outside of the drive shaft,wherein a spring element acts as a further dosing means providingadditional closing force between these guide housings and adjacentlyarranged housing parts of the receiving housing.

Advantageously, the arrangement can be made such in this case that therelevant spring element permits compensating motions of the receivinghousing relative to the gap-shaped passage opening of the relevantpartial element. The adjustment thus forms a kind of “pendulum device”,which permits an additional angle compensation.

In a particularly advantageous manner, the compensating motion can occurin parallel to the closing direction of the relevant dosing means of thespindle drive or at a tilt angle, for which the receiving housing istilted to close a partial element at least partially more in thedirection of the adjacent filter element and the other partial elementof a pair moves away from the element.

A prestressed compression spring can be used for a parallel dosingmotion, and for a tilting motion, an elastically yielding sealingelement, which comprises the fluid guide of the partial element whenentering the internal fluid guide of the drive shaft, can be used.

In advantageous exemplary embodiments, a receiving plate interactingwith the spindle drive is used to implement the tilting motion, the freeends of which receiving plate are connected to the receiving housing andwhich, while maintaining a distance, at least partially comprises thereceiving housing, viewed in the direction of the drive shaft.

In exemplary embodiments having dosing means of the spindle drivelaterally guided along the drive shaft, the arrangement may beadvantageously made such that the receiving plate is connected to tworods assigned to the spindle drive, which are guided in the outer guidehousings located at the drive shaft and which can be attached to theguide housing by means of a toggle drive to lock the adjustment inplace.

Below the invention is explained in detail with reference to exemplaryembodiments shown in the drawing.

In the Figures:

FIG. 1 shows a vertical section of an exemplary embodiment of the filterdevice according to the invention, drawn broken and slightly offset fromthe center plane;

FIG. 2 shows a perspective oblique view of the device part shown in FIG.1, the housing wall of which is cut open;

FIG. 3 shows a vertical section of the device part shown in FIGS. 1 and2 with a central sectional plane;

FIG. 4 shows a perspective oblique view of the device part of FIGS. 1 to3 cut along the central plane;

FIG. 5 shows a perspective oblique view of a longitudinal section of thedrive shaft and of a backwash element located thereon according to asecond exemplary embodiment of the filter device according to theinvention;

FIG. 6 shows a perspective oblique view of the device part of the secondexemplary embodiment shown in FIG. 5, wherein device parts are drawn cutaway in the area of a guide housing located laterally at the driveshaft;

FIG. 7 shows a perspective oblique view of the device part of the secondexemplary embodiment, cut away in a central vertical plane;

FIG. 8 shows a side view of a backwash element with an assignedadjustment device of the second exemplary embodiment, in a separaterepresentation without a drive shaft, drawn at a smaller scale;

FIG. 9 shows a plan view of the backwash element of FIG. 8 mounted atthe drive shaft shown in cross section;

FIGS. 10 and 11 show a side view and a longitudinal section of thespindle drive of the guide housing assigned to adjustment device of thesecond exemplary embodiment;

FIG. 12 shows a side view of a longitudinal section of the drive shaftof the second exemplary embodiment having a backwash element locatedthereon;

FIG. 13 shows the side view of FIG. 12 in a partially broken-away andsectioned drawing;

FIG. 14 shows an enlarged partial section of the area designated XIV inFIG. 13.

FIGS. 1 to 4 show a first exemplary embodiment of the filter deviceaccording to the invention. It has a filter housing designated as awhole by 1, the construction of which corresponds to the relevant,mentioned prior art (cf, FIG. 1 of the mentioned DE 202016003089 U1).The truncated representations of the filter housing 1 in FIGS. 1 to 4,therefore, show only a part of the housing main part 3 and of adownwardly adjoining housing bottom part or entry part 5. A first filterelement 7 and a second overlying filter element 9 are arranged in themain part 3, of which filter elements only the lower one is completelyvisible. At the bottom part 5, there is a lateral inlet 11, throughwhich the unfiltered matter flows into the bottom part 5 and afterflowing through an input filter 13, which is provided in maritimeapplications as a so-called fish trap, flows into the inner cavity ofthe filter elements 7 and 9 via passages 15, which cavity is encompassedby the inside 17 of filter material(s) of the filter elements. Duringthe filtration process, the fluid flows from the inside to the outsidethrough the finer material, the fluid reaches the chamber 18encompassing the filter elements 7, 9, which forms the filtered side inthe main part 3, from which it flows off via a lateral outlet 19 forfiltrate.

As usual in the state of the art, a backwash element is provided forevery filter element 7 and 9 at a drive shaft 20 formed by a squaretube, which contains two partial backwash elements 22 arranged one abovethe other in a receiving housing 21. The partial elements 22, which arestate of the art and therefore only schematically outlined in thefigures, are formed in the usual way by a type of scraper, theslot-shaped passage opening of which runs in parallel to the axis ofrotation of the drive shaft 20, and which are guided along the inside 17of the filter elements 7, 9 in contact with the latter during arotational motion of the drive shaft 20. The passage opening continuesin the interior of the partial elements 22 in a flow chamber, which isconnected to the interior of the drive shaft 20 via one fluid guide 23each. These fluid guides 23 are guided longitudinally in a telescopicmanner in a connector part 24 located at the drive shaft 20. The driveshaft 20 can be driven according to the state of the art and isrotatably mounted, wherein only one lower pivot bearing 25 of thebearings is visible, at which the lower end of the drive shaft 20transitions into a sludge discharge pipe 26.

An adjustment device having a spindle drive is provided for closing thereceiving housing 21 having the backwash elements 22, i.e. for theadjustment of the distance of the gap-shaped passage openings of thepartial elements 22 of the rotation axis 16 of the drive shaft 20. Thespindle drive has, in the example of FIGS. 1 to 4, a threaded spindle 27which can be fed through the drive shaft 20 in the directionperpendicular to the rotation axis 16. The threaded spindle 27 forms adosing means, the end of which facing the receiving housing 21 isconnected to the latter in the middle between the partial elements 22.The receiving housing 21 has the shape of a bar-like body having longsides 28 and 29 (FIG. 2), which extend in parallel to the axis ofrotation 16 of the drive shaft 20, wherein the partial elements 22 arearranged one above the other inside the receiving housing 21, and thevertical axis is arranged in alignment between the long sides 25, 29.The fluid guides 23 of the partial elements 22 have an output tube 30 atthe fluid guide 23, which, cf. FIGS. 3 and 4, is telescopically guidedin the associated connector part 24 of the drive shaft 20. The end ofthe threaded spindle 27 facing the receiving housing 21 is connected toa plate 31 of the receiving housing 21, which forms the end wall of thereceiving housing 21 facing the drive shaft 20. The connection point 37to the spindle drive 27 is in the middle between the fluid guides 23.For the position adjustment of the threaded spindle 27, as shown mostclearly in FIG. 4, a nut 32 is attached to the outside of the driveshaft 20 facing the receiving housing 21, which is in threadedengagement with the external thread of the threaded spindle 27. On theopposite outer side 33 of the drive shaft 20 a knurled nut 34 is inthreaded engagement with the external thread of the threaded spindle 27.A manually operable rotary lever 35 is located at the free end of thethreaded spindle 27 projecting beyond the knurled nut 34.

The connection 37 of the end of the threaded spindle 27 to the plate 31of the receiving housing 21 is designed such that the spindle 27 can berotated relative to the receiving housing 21, but the spindle 27 limitsthe radially outwardly extended position of the receiving housing 21.This position can be adjusted in that for a not tightened knurled nut 34when the threaded spindle 27 is rotated by means of the lever 35 due tothe threaded engagement with the nut 32, the axial position of thespindle 27 and thus the fully extended end position of the receivinghousing 21 are set. By tightening the knurled nut 34, the rotationalposition of the spindle 27 is secured and the setting is locked. If, asshown in FIGS. 1 and 2, a spring element 36 is inserted at the fluidguides 23 of the partial elements 22, which spring element stresses thereceiving housing 21 radially outwards for closing, the connection 37between the spindle 27 and the plate 31 is advantageously implemented asa type of floating bearing, which limits a motion of the receivinghousing 21 radially outwardly in a form-fitting manner, but permits atilting motion of the receiving housing 21 about an axis transverse tothe main axis and optionally provides an axial clearance for a springtravel that is directed radially inwards.

The second exemplary embodiment shown in FIGS. 5 to 15 in particularprovides compensating and tilting motions. As in the first exemplaryembodiment, the adjustment device has a spindle drive, which can beactuated manually from the outside of the drive shaft 20. Unlike thefirst example, the receiving housing 21 of the partial elements 22 doesnot have the form of a beam-shaped bar body, but its outer shape isformed by the two superposed flow funnels of the partial backwashelements 22, which are interconnected by a front plate 41 at theradially outer side. To interact with the spindle drive, a receivingplate 43 extending in parallel to the end plate 41 is provided, whichhas lateral wings 44, which partially encompass the partial elements 22and are interconnected via a central web 45 extending through the gapbetween the partial elements 22. The ends of the wings 44 are eachfirmly connected to the end plate 41 of the receiving housing 21.Another difference to the example described first is that the threadedspindle of the spindle drive is not fed through the drive shaft 20. Asmost clearly shown in FIG. 7 in conjunction with FIGS. 5 and 6, athreaded spindle in the form of a pressure screw 47 is provided, whichhas a knurled head 49, which allows a manual rotational adjustingmotion. As FIG. 10 shows, the pressure screw 47 has a non-threaded endsection 51 and a threaded section 52. The non-threaded end section 51,which can be rotated in a guide body 54, is supported at its free end ata pressure plate 53, which is located at the outside of the drive shaft20. The threaded portion 52 is in threaded engagement with an internalthread in a cross bar 55. The cross bar 55 extends beyond the width ofthe facing outside of the drive shaft 20 and its protruding ends formthe connection points for a rod 57. These are each longitudinally guidedin a guide housing 59 in a direction perpendicular to the axis ofrotation 16 of the drive shaft 20. As shown in FIGS. 5 and 6 inconjunction with FIGS. 10 and 11, a fastening bolt 63 penetrates asleeve 61 and an annular disc 60 at the respective connections of thecross bar 55 to the rods 57. In a corresponding manner, the other end ofthe rods 57 is connected to the receiving plate 43 by a bolt, at aposition which is located centrally between the ends of the wings 44. Inthis bolted connection, a fastening bolt 43 extends through anelastomeric sleeve body 66, such that a flexible support of thereceiving housing 21 is formed relative to the drive shaft 20 on thereceiving plate 43.

As in the first exemplary embodiment, the fluid guides 23 of thesub-elements 22 are guided in a telescopically displaceable manner inthe assigned connector part 24 of the drive shaft 20. As with theconnection between the rods 57 and the receiving plate 43 of thereceiving housing 21, where a flexible support 66 is formed by theelastomeric sleeve body used, a flexible guide is also provided in theguide of the fluid connections 23 in the connecting parts 24 of thedrive shaft 20. As can be seen in FIGS. 13 and 14, a radial play seeFIG. 14 at 65) is provided between the fluid guide 23 and the connectingpart 24 and a resilient sealing element 67 is used, for which there is afree space available in the connecting part 24 for the yielding of thesealing element 67.

As in the first exemplary embodiment, the receiving housing 21 isprestressed by the spring elements 36 encompassing the fluid guides 23for a radially outwardly extending adjustment, which is limited by theposition of the dosing means connected to the spindle drive. In the thisexemplary embodiment, this is the position of the rods 57 laterallyguided in the receiving housings 59. These are supported against theforce of the spring elements 36 by means of the pressure bolt 47 and thecross-bar 55 in threaded engagement with the pressure bolt. By manuallyturning the pressure bolt 47 using the knurled head 49 in one or theother direction of rotation, the axial position of the rods 57 can beadjusted. The flexible mounting of the rods 57 at the receiving plate 43of the receiving housing 21 in conjunction with the shown, flexibleguidance of the fluid guides 23 at the connecting parts 24 of the driveshaft 20 permits compensating motions, such as a tilt angle ofplus/minus 1 degree of the end plate 41 of the receiving housing 21 in aplane parallel to the axis of the drive shaft 20. FIGS. 5 and 8 and 9show for each guide housing 59 a toggle drive 69, which is attached tothe end of the relevant guide housing 59 facing the receiving housing 21and can be actuated manually to lock the position of the rod 57 byclamping.

The filter device according to the invention can be used for otherapplications for which it is suitable in addition to the filtration oflubricating oil. In addition to the already mentioned maritime usage inwhich ballast water of ships is purified, the device can also be usedfor the treatment of process water.

1. A filter device having a filter housing (1), having a fluid inlet(11) for unfiltered matter and having a fluid outlet (19) for filteredmatter and at least one filter element (7, 9) of one or more partsaccommodated in the filter housing (1), which filter element can becleaned using at least one backwash element (21) in counter current tothe direction of filtration, which can be moved by means of afluid-conveying drive shaft (20) of a rotary drive at the inside (17) ofthe relevant filter element (7, 9) and which has, at the end adjacent tothis inside (17), a gap-shaped passage opening, which is parallel to theaxis of rotation (16) of the drive shaft (20) and which opens into aflow chamber connected to the drive shaft (20) in a fluid-conveyingmanner, characterized in that the distance between the backwash element(21) and the adjacent assignable filter element (7, 9) can bepredetermined by means of an adjustment device (27; 47).
 2. The filterdevice according to claim 1, characterized in that the adjusting devicehas a spindle drive (27; 47), which can be actuated manually from oneside of the drive shaft (20) and has closing means, which act at theother side of the drive shaft (20) at the individual backwash element(21).
 3. The filter device according to claim 1, characterized in thatthe spindle (27) of the spindle drive executing its adjustment motionextends through the inner fluid guide of the drive shaft (20) and itsend (37) extending through the drive shaft (20) forms the part of theclosing means acting at the individual backwash element (21).
 4. Thefilter device according to claim 1, characterized in that closing means(57) that can be moved by the spindle drive (47) can be guided pastoutsides of the drive shaft (20).
 5. The filter device according toclaim 1, characterized in that the backwash element may have a receivinghousing (21), with which the spindle drive (27; 47) engages with itsrespective closing means (37; 57) and in which the at least two partialbackwash elements (22) are accommodated, and that one fluid guide (23)is assigned to every partial element (22), which, guided longitudinally,engages in every traversing position of the receiving housing (21) withthe internal fluid guide (24) of the drive shaft (20).
 6. The filterdevice according to claim 1, characterized in that the spindle drive(27) uses its respective closing means (37) to act on the receivinghousing (21) between the fluid guides (23) of a pair of partial elements(22).
 7. The filter device according to claim 1, characterized in thatthe respective closing means (57) for one partial element (22) each ismovably guided in every guide housing (59) mounted at the outside of thedrive shaft (20), and that a spring element (36) acts as a furtherclosing means providing additional closing force between these guidehousings (59) and adjacently arranged housing parts of the receivinghousing (21).
 8. The filter device according to claim 1, characterizedin that the relevant spring element (36) permits compensating motions ofthe receiving housing (21) relative to the gap-shaped passage opening ofthe relevant partial element (22).
 9. The filter device according toclaim 1, characterized in that the compensating motion can occur inparallel to the closing direction of the relevant closing means (57) ofthe spindle drive (47) or at a tilt angle, for which the receivinghousing (21) is tilted to close a partial element (22) at leastpartially more in the direction of the adjacent filter element (7, 9)and the other partial element (22) of a pair moves away from the element(7, 9).
 10. The filter device according to claim 1, characterized inthat a prestressed compression spring (36) can be used for a parallelclosing motion, and for a tilting motion, an elastically yieldingsealing element (67), which comprises the fluid guide (23) of thepartial element (22) when entering the internal fluid guide (24) of thedrive shaft (20), can be used.
 11. The filter device according to claim1, characterized in that a receiving plate interacting with the spindledrive (47) is used to implement the tilting motion, the free ends (44)of which receiving plate (43) are connected to the receiving housing(21) and which, while maintaining a distance, at least partiallycomprises the receiving housing (21), viewed in the direction of thedrive shaft (20).
 12. The filter device according to claim 1,characterized in that the receiving plate (43) is connected to two rods(57) assigned to the spindle drive (47), which are guided in the outerguide housings (59) located at the drive shaft (22) as closing means ofthe spindle drive (47) and which can be attached to the guide housing(59) by means of a toggle drive (69) to lock the adjustment in place.